Hello Gaz,
You do not have to manually add anything.
Please, check your %APPDATA% location, the Remote Utilities Files folder. In that folder there is a file connections_4.xml . This is your general address book that you can import back to your Viewer (Manage -> Manual import command).
If this file is empty or corrupted for some reason, please check the backups folder. This folder contains daily backups of your address book. You can restore the latest backup as described
here.
Hope that helps.